assume cs:code, ds:data, ss:stack

data segment
      dw    0123H, 0456H
data ends

stack segment
      dw    0, 0
stack ends     

code segment

start:      mov ax, stack
             mov ss, ax
             mov sp, 16
             mov ax, data
             mov ds, ax
             push ds:[0]
             push ds:[2]
             pop ds:[2]
             pop ds:[0]
             
             mov ax, 4c00h
             int 21h
code ends
end start